The rails I have made for my models have generally been wooden which allowed me to make them much longer lengths than would be possible with my 3d printer. However on a couple of occasions I have designed and 3D printed some short rail lengths for displaying the models I have given to other people. Wooden rails are fine, even essential, for animation where long runs are necessary and fine detail isn’t. But for display, the 3D printed rails win with their greater detail. So I was prompted to develop a parametric track model which I could easily use to match my own models as well as other standard scales such as the OS-Railway system or the garden railway scale. I suspect it may be tricky getting a good print for smaller scales such as HO, but the parametricness will still work down at that scale.

You can find a more detailed explanation of this project on my website.

The General Parameters

• RailHt = Height of the Rail
• TrakGage = Track Gauge. This is the distance between the inside edges of the rail head NOT the distance between rail centrelines. For The Opensource Railway, this is 32mm. For my narrow gauge models it is 36mm, and for my 1:24 railcar chassis models, it is 60mm.
• SlprLn = Sleeper length.
• SlprHt = Sleeper height.
• SlprWd is the width of the sleepers.
• NoSlprs is the number of sleepers in the section of rail to be produced.

Curved Track Parameters

• CurveRad = Radius of railway centreline
• CurveSegAng = The angle of the track segment being produced. You will need to choose this to suit your printer bed size.

End Types and Options

TrkTyp = Type of track end style.

• Setting TrkTyp = 1 will select the option where the track join is between the sleepers.
• Setting TrkTyp = 2 will select track type 2 where the join is down the centre of one of the sleepers. This is especially useful if you opt not to print sleepers.

SleepersYN is a flag for having sleepers or not. Setting this to “1” will generate a model complete with sleepers. Setting it to anything else will produce a model that doesn’t include sleepers but includes the sleeper attachment pad details.

Other Parametric Track Models in this series are:

• Standard Straight Track https://www.thingiverse.com/thing:3400628
• OS-Railway Straight Track https://www.thingiverse.com/thing:3400784
• OS-Railway Curved Track https://www.thingiverse.com/thing:3400779

If you have used the parametric tool to produce some rails without sleepers, you may want to look at the Parametric Track Setting Tool.